1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Copyright (c) 2011-2016 Synaptics Incorporated 4 * Copyright (c) 2011 Unixphere 5 */ 6 7 #include <linux/kernel.h> 8 #include <linux/device.h> 9 #include <linux/irq.h> 10 #include <linux/irqdomain.h> 11 #include <linux/list.h> 12 #include <linux/pm.h> 13 #include <linux/rmi.h> 14 #include <linux/slab.h> 15 #include <linux/types.h> 16 #include <linux/of.h> 17 #include "rmi_bus.h" 18 #include "rmi_driver.h" 19 20 static int debug_flags; 21 module_param(debug_flags, int, 0644); 22 MODULE_PARM_DESC(debug_flags, "control debugging information"); 23 24 void rmi_dbg(int flags, struct device *dev, const char *fmt, ...) 25 { 26 struct va_format vaf; 27 va_list args; 28 29 if (flags & debug_flags) { 30 va_start(args, fmt); 31 32 vaf.fmt = fmt; 33 vaf.va = &args; 34 35 dev_printk(KERN_DEBUG, dev, "%pV", &vaf); 36 37 va_end(args); 38 } 39 } 40 EXPORT_SYMBOL_GPL(rmi_dbg); 41 42 /* 43 * RMI Physical devices 44 * 45 * Physical RMI device consists of several functions serving particular 46 * purpose. For example F11 is a 2D touch sensor while F01 is a generic 47 * function present in every RMI device. 48 */ 49 50 static void rmi_release_device(struct device *dev) 51 { 52 struct rmi_device *rmi_dev = to_rmi_device(dev); 53 54 kfree(rmi_dev); 55 } 56 57 static const struct device_type rmi_device_type = { 58 .name = "rmi4_sensor", 59 .release = rmi_release_device, 60 }; 61 62 bool rmi_is_physical_device(struct device *dev) 63 { 64 return dev->type == &rmi_device_type; 65 } 66 67 /** 68 * rmi_register_transport_device - register a transport device connection 69 * on the RMI bus. Transport drivers provide communication from the devices 70 * on a bus (such as SPI, I2C, and so on) to the RMI4 sensor. 71 * 72 * @xport: the transport device to register 73 */ 74 int rmi_register_transport_device(struct rmi_transport_dev *xport) 75 { 76 static atomic_t transport_device_count = ATOMIC_INIT(0); 77 struct rmi_device *rmi_dev; 78 int error; 79 80 rmi_dev = kzalloc(sizeof(struct rmi_device), GFP_KERNEL); 81 if (!rmi_dev) 82 return -ENOMEM; 83 84 device_initialize(&rmi_dev->dev); 85 86 rmi_dev->xport = xport; 87 rmi_dev->number = atomic_inc_return(&transport_device_count) - 1; 88 89 dev_set_name(&rmi_dev->dev, "rmi4-%02d", rmi_dev->number); 90 91 rmi_dev->dev.bus = &rmi_bus_type; 92 rmi_dev->dev.type = &rmi_device_type; 93 rmi_dev->dev.parent = xport->dev; 94 95 xport->rmi_dev = rmi_dev; 96 97 error = device_add(&rmi_dev->dev); 98 if (error) 99 goto err_put_device; 100 101 rmi_dbg(RMI_DEBUG_CORE, xport->dev, 102 "%s: Registered %s as %s.\n", __func__, 103 dev_name(rmi_dev->xport->dev), dev_name(&rmi_dev->dev)); 104 105 return 0; 106 107 err_put_device: 108 put_device(&rmi_dev->dev); 109 return error; 110 } 111 EXPORT_SYMBOL_GPL(rmi_register_transport_device); 112 113 /** 114 * rmi_unregister_transport_device - unregister a transport device connection 115 * @xport: the transport driver to unregister 116 * 117 */ 118 void rmi_unregister_transport_device(struct rmi_transport_dev *xport) 119 { 120 struct rmi_device *rmi_dev = xport->rmi_dev; 121 122 device_del(&rmi_dev->dev); 123 put_device(&rmi_dev->dev); 124 } 125 EXPORT_SYMBOL(rmi_unregister_transport_device); 126 127 128 /* Function specific stuff */ 129 130 static void rmi_release_function(struct device *dev) 131 { 132 struct rmi_function *fn = to_rmi_function(dev); 133 134 kfree(fn); 135 } 136 137 static const struct device_type rmi_function_type = { 138 .name = "rmi4_function", 139 .release = rmi_release_function, 140 }; 141 142 bool rmi_is_function_device(struct device *dev) 143 { 144 return dev->type == &rmi_function_type; 145 } 146 147 static int rmi_function_match(struct device *dev, struct device_driver *drv) 148 { 149 struct rmi_function_handler *handler = to_rmi_function_handler(drv); 150 struct rmi_function *fn = to_rmi_function(dev); 151 152 return fn->fd.function_number == handler->func; 153 } 154 155 #ifdef CONFIG_OF 156 static void rmi_function_of_probe(struct rmi_function *fn) 157 { 158 char of_name[9]; 159 struct device_node *node = fn->rmi_dev->xport->dev->of_node; 160 161 snprintf(of_name, sizeof(of_name), "rmi4-f%02x", 162 fn->fd.function_number); 163 fn->dev.of_node = of_get_child_by_name(node, of_name); 164 } 165 #else 166 static inline void rmi_function_of_probe(struct rmi_function *fn) 167 {} 168 #endif 169 170 static struct irq_chip rmi_irq_chip = { 171 .name = "rmi4", 172 }; 173 174 static int rmi_create_function_irq(struct rmi_function *fn, 175 struct rmi_function_handler *handler) 176 { 177 struct rmi_driver_data *drvdata = dev_get_drvdata(&fn->rmi_dev->dev); 178 int i, error; 179 180 for (i = 0; i < fn->num_of_irqs; i++) { 181 set_bit(fn->irq_pos + i, fn->irq_mask); 182 183 fn->irq[i] = irq_create_mapping(drvdata->irqdomain, 184 fn->irq_pos + i); 185 186 irq_set_chip_data(fn->irq[i], fn); 187 irq_set_chip_and_handler(fn->irq[i], &rmi_irq_chip, 188 handle_simple_irq); 189 irq_set_nested_thread(fn->irq[i], 1); 190 191 error = devm_request_threaded_irq(&fn->dev, fn->irq[i], NULL, 192 handler->attention, IRQF_ONESHOT, 193 dev_name(&fn->dev), fn); 194 if (error) { 195 dev_err(&fn->dev, "Error %d registering IRQ\n", error); 196 return error; 197 } 198 } 199 200 return 0; 201 } 202 203 static int rmi_function_probe(struct device *dev) 204 { 205 struct rmi_function *fn = to_rmi_function(dev); 206 struct rmi_function_handler *handler = 207 to_rmi_function_handler(dev->driver); 208 int error; 209 210 rmi_function_of_probe(fn); 211 212 if (handler->probe) { 213 error = handler->probe(fn); 214 if (error) 215 return error; 216 } 217 218 if (fn->num_of_irqs && handler->attention) { 219 error = rmi_create_function_irq(fn, handler); 220 if (error) 221 return error; 222 } 223 224 return 0; 225 } 226 227 static int rmi_function_remove(struct device *dev) 228 { 229 struct rmi_function *fn = to_rmi_function(dev); 230 struct rmi_function_handler *handler = 231 to_rmi_function_handler(dev->driver); 232 233 if (handler->remove) 234 handler->remove(fn); 235 236 return 0; 237 } 238 239 int rmi_register_function(struct rmi_function *fn) 240 { 241 struct rmi_device *rmi_dev = fn->rmi_dev; 242 int error; 243 244 device_initialize(&fn->dev); 245 246 dev_set_name(&fn->dev, "%s.fn%02x", 247 dev_name(&rmi_dev->dev), fn->fd.function_number); 248 249 fn->dev.parent = &rmi_dev->dev; 250 fn->dev.type = &rmi_function_type; 251 fn->dev.bus = &rmi_bus_type; 252 253 error = device_add(&fn->dev); 254 if (error) { 255 dev_err(&rmi_dev->dev, 256 "Failed device_register function device %s\n", 257 dev_name(&fn->dev)); 258 goto err_put_device; 259 } 260 261 rmi_dbg(RMI_DEBUG_CORE, &rmi_dev->dev, "Registered F%02X.\n", 262 fn->fd.function_number); 263 264 return 0; 265 266 err_put_device: 267 put_device(&fn->dev); 268 return error; 269 } 270 271 void rmi_unregister_function(struct rmi_function *fn) 272 { 273 int i; 274 275 rmi_dbg(RMI_DEBUG_CORE, &fn->dev, "Unregistering F%02X.\n", 276 fn->fd.function_number); 277 278 device_del(&fn->dev); 279 of_node_put(fn->dev.of_node); 280 281 for (i = 0; i < fn->num_of_irqs; i++) 282 irq_dispose_mapping(fn->irq[i]); 283 284 put_device(&fn->dev); 285 } 286 287 /** 288 * __rmi_register_function_handler - register a handler for an RMI function 289 * @handler: RMI handler that should be registered. 290 * @owner: pointer to module that implements the handler 291 * @mod_name: name of the module implementing the handler 292 * 293 * This function performs additional setup of RMI function handler and 294 * registers it with the RMI core so that it can be bound to 295 * RMI function devices. 296 */ 297 int __rmi_register_function_handler(struct rmi_function_handler *handler, 298 struct module *owner, 299 const char *mod_name) 300 { 301 struct device_driver *driver = &handler->driver; 302 int error; 303 304 driver->bus = &rmi_bus_type; 305 driver->owner = owner; 306 driver->mod_name = mod_name; 307 driver->probe = rmi_function_probe; 308 driver->remove = rmi_function_remove; 309 310 error = driver_register(driver); 311 if (error) { 312 pr_err("driver_register() failed for %s, error: %d\n", 313 driver->name, error); 314 return error; 315 } 316 317 return 0; 318 } 319 EXPORT_SYMBOL_GPL(__rmi_register_function_handler); 320 321 /** 322 * rmi_unregister_function_handler - unregister given RMI function handler 323 * @handler: RMI handler that should be unregistered. 324 * 325 * This function unregisters given function handler from RMI core which 326 * causes it to be unbound from the function devices. 327 */ 328 void rmi_unregister_function_handler(struct rmi_function_handler *handler) 329 { 330 driver_unregister(&handler->driver); 331 } 332 EXPORT_SYMBOL_GPL(rmi_unregister_function_handler); 333 334 /* Bus specific stuff */ 335 336 static int rmi_bus_match(struct device *dev, struct device_driver *drv) 337 { 338 bool physical = rmi_is_physical_device(dev); 339 340 /* First see if types are not compatible */ 341 if (physical != rmi_is_physical_driver(drv)) 342 return 0; 343 344 return physical || rmi_function_match(dev, drv); 345 } 346 347 struct bus_type rmi_bus_type = { 348 .match = rmi_bus_match, 349 .name = "rmi4", 350 }; 351 352 static struct rmi_function_handler *fn_handlers[] = { 353 &rmi_f01_handler, 354 #ifdef CONFIG_RMI4_F03 355 &rmi_f03_handler, 356 #endif 357 #ifdef CONFIG_RMI4_F11 358 &rmi_f11_handler, 359 #endif 360 #ifdef CONFIG_RMI4_F12 361 &rmi_f12_handler, 362 #endif 363 #ifdef CONFIG_RMI4_F30 364 &rmi_f30_handler, 365 #endif 366 #ifdef CONFIG_RMI4_F34 367 &rmi_f34_handler, 368 #endif 369 #ifdef CONFIG_RMI4_F3A 370 &rmi_f3a_handler, 371 #endif 372 #ifdef CONFIG_RMI4_F54 373 &rmi_f54_handler, 374 #endif 375 #ifdef CONFIG_RMI4_F55 376 &rmi_f55_handler, 377 #endif 378 }; 379 380 static void __rmi_unregister_function_handlers(int start_idx) 381 { 382 int i; 383 384 for (i = start_idx; i >= 0; i--) 385 rmi_unregister_function_handler(fn_handlers[i]); 386 } 387 388 static void rmi_unregister_function_handlers(void) 389 { 390 __rmi_unregister_function_handlers(ARRAY_SIZE(fn_handlers) - 1); 391 } 392 393 static int rmi_register_function_handlers(void) 394 { 395 int ret; 396 int i; 397 398 for (i = 0; i < ARRAY_SIZE(fn_handlers); i++) { 399 ret = rmi_register_function_handler(fn_handlers[i]); 400 if (ret) { 401 pr_err("%s: error registering the RMI F%02x handler: %d\n", 402 __func__, fn_handlers[i]->func, ret); 403 goto err_unregister_function_handlers; 404 } 405 } 406 407 return 0; 408 409 err_unregister_function_handlers: 410 __rmi_unregister_function_handlers(i - 1); 411 return ret; 412 } 413 414 int rmi_of_property_read_u32(struct device *dev, u32 *result, 415 const char *prop, bool optional) 416 { 417 int retval; 418 u32 val = 0; 419 420 retval = of_property_read_u32(dev->of_node, prop, &val); 421 if (retval && (!optional && retval == -EINVAL)) { 422 dev_err(dev, "Failed to get %s value: %d\n", 423 prop, retval); 424 return retval; 425 } 426 *result = val; 427 428 return 0; 429 } 430 EXPORT_SYMBOL_GPL(rmi_of_property_read_u32); 431 432 static int __init rmi_bus_init(void) 433 { 434 int error; 435 436 error = bus_register(&rmi_bus_type); 437 if (error) { 438 pr_err("%s: error registering the RMI bus: %d\n", 439 __func__, error); 440 return error; 441 } 442 443 error = rmi_register_function_handlers(); 444 if (error) 445 goto err_unregister_bus; 446 447 error = rmi_register_physical_driver(); 448 if (error) { 449 pr_err("%s: error registering the RMI physical driver: %d\n", 450 __func__, error); 451 goto err_unregister_bus; 452 } 453 454 return 0; 455 456 err_unregister_bus: 457 bus_unregister(&rmi_bus_type); 458 return error; 459 } 460 module_init(rmi_bus_init); 461 462 static void __exit rmi_bus_exit(void) 463 { 464 /* 465 * We should only ever get here if all drivers are unloaded, so 466 * all we have to do at this point is unregister ourselves. 467 */ 468 469 rmi_unregister_physical_driver(); 470 rmi_unregister_function_handlers(); 471 bus_unregister(&rmi_bus_type); 472 } 473 module_exit(rmi_bus_exit); 474 475 MODULE_AUTHOR("Christopher Heiny <cheiny@synaptics.com"); 476 MODULE_AUTHOR("Andrew Duggan <aduggan@synaptics.com"); 477 MODULE_DESCRIPTION("RMI bus"); 478 MODULE_LICENSE("GPL"); 479